1. Field of the Invention
The present invention is directed to an inlet system for a mass spectrometer that facilitates analysis, and a method for analyzing a gas by mass spectrometry.
2. Description of Related Art
Mass spectrometry systems and mass spectrometry methods for analysis are both known in the art, and are utilized to analyze chemical compounds including gases made up of various components. In particular, mass spectrometric analysis techniques allow the components of the gas being analyzed to be identified and measured. Mass spectrometry systems and techniques offer various advantages that are not provided by many other analytical equipment and techniques. These advantages include a very fast response time, and the ability to analyze variety of gas components using the same equipment. Moreover, mass spectrometry systems are relatively economical, thereby allowing analysis of chemical compounds such as gases, in a cost effective manner.
For example, U.S. Pat. No. 4,646,412 to Ebner et al. discloses an apparatus and a method for carrying out catalysis and catalyzed chemical reactions. In particular, the reference discloses a reactor with a catalyst zone, under vacuum, into which a very rapid pulse of reactant gas is pulsed. The products are analyzed by mass spectrometry. The reference further discloses that the apparatus and method can detect reaction intermediates and products, and can indicate their sequence of production.
U.S. Pat. No. 5,565,171 to Dovichi et al. discloses a reactor for reacting, and analyzing, a sample organic molecule. The reference discloses that the reactor includes a continuous capillary connected between two valves that control fluid flow in the capillary. One part of the capillary is disclosed as forming a reaction chamber where the sample may be immobilized to allow subsequent reaction with reagents that are supplied through the valves. Another part of the capillary is disclosed as passing through, or terminating in, a detector portion of a mass spectrometer.
In view of the above noted advantages, mass spectrometry systems and methods have been implemented to analyze, and to measure, gas composition in exhaust gases of internal combustion engines. In particular, mass spectrometry systems and methods have been used to analyze and measure gas components in exhaust gas recirculation (EGR) manifolds, as well as in exhaust after-treatment devices such as NOx adsorbers.
However, some components of the exhaust gas that are generated by an internal combustion engine may be difficult to measure, even when mass spectrometry equipment and methods of analysis are used. Some components of exhaust gas such as various hydrocarbons cannot be analyzed or measured accurately using mass spectrometry equipment and methods of analysis.
Therefore, in view of the above, there exists an unfulfilled need for a mass spectrometry system for analyzing components of a gas that overcomes the limitations of conventional mass spectrometry systems. There also exists an unfulfilled need for a method of analyzing a gas by mass spectrometry that overcomes the limitations of conventional mass spectrometry techniques, and further allows the above noted analysis and measurements to be attained.